THE WHEAT GRAIN AND PLANT 21 



injured when fertilization takes .place in rainy weather. The 

 water probably finds its way wi%in the involucre, and the 

 pollen grains are either imperfectly retained, or their germi- 

 nation is irregular. The process of fertilization generally oc- 

 curs early in the morning, and may require less than an hour 

 of time. After its completion the ovule (seed) grows very 

 rapidly to maturity. The embryo develops first, and then the 

 endosperm. 



The Most Favorable Ripening of wheat requires a mild tem- 

 perature and a slightly clouded sky. A high telS^e^iiture the 

 month before wheat is ripe diminishes the yield, and in partic- 

 ular prevents the formation of starch. There is a real, though 

 small, loss in wheat from the period when it is "ripe" to the 

 time when it is dead ripe, and it is claimed that this loss does 

 not result from careless handling, or from drying of the grain. 1 

 Deherain offers the explanation that "all the organs of a 

 plant respire by the aid of the oxygen of the air consuming 

 some of their principles. In the seed the combustion chiefly 

 affects the starch, and a crop which remains standing long 

 diminishes in weight both by the loss of seeds that fall and by 

 the slow combustion which continues as long as desiccation is 

 not produced." What is lost in quantity, however, is perhaps 

 more than gained in quality, for the best flour can be obtained 

 from dead ripe wheat only. Such flour has a better color, and 

 will take more water in bread-making. If the grain is cut be- 

 fore ripe, the most serious feature is increased acidity in the 

 flour. This interferes with fermentation in bread-making, and 

 is liable to make the bread sour or dark. 



The Rate of Multiplication of Wheat. Paley gave 300 grains 

 harvested from one grain sown as a moderate estimate; 400 as 

 a possible one; and 10 to 12 as a practical one. Herodotus 

 said that on the irrigated land of Assyria, wheat yielded from 

 two to three hundred fold, and grew to giant size. Fifty 

 grains of wheat, selected from one spike, were planted, and 

 the 30 grains which grew produced 14% ounces of wheat. 

 This was sown the next year, and produced 5 pecks of grain, 

 which in turn produced 45 bushels the subsequent year. The 

 45 bushels produced 537 bushels in another year, enough seed 



1 Kedzie, Kept. Mich. Board Agr., 1881-2, p. 337; Mich. Bui. 191, 

 p. 160; Neb. Bui. 32, p. 97. 



